Find a penny, pick it up, and all day you'll have good luck.

A penny saved is a penny earned.

as pretty as penny

A Penny for your thoughts (口)你发呆想什么呢?

Penny wise and pound foolish 小事聪明,大事糊涂

In for a penny, in for a pound (谚)一不做二不休

Pennies from heaven 天上掉下来的钱, 意外之财

a bad penny 反复出现的讨厌的人/物

penny pincher 吝啬鬼